drivers/video/fbdev/cg3.c

   1 // SPDX-License-Identifier: GPL-2.0-only
   2 /* cg3.c: CGTHREE frame buffer driver
   3  *
   4  * Copyright (C) 2003, 2006 David S. Miller (davem@davemloft.net)
   5  * Copyright (C) 1996,1998 Jakub Jelinek (jj@ultra.linux.cz)
   6  * Copyright (C) 1996 Miguel de Icaza (miguel@nuclecu.unam.mx)
   7  * Copyright (C) 1997 Eddie C. Dost (ecd@skynet.be)
   8  *
   9  * Driver layout based loosely on tgafb.c, see that file for credits.
  10  */
  11
  12 #include <linux/module.h>
  13 #include <linux/kernel.h>
  14 #include <linux/errno.h>
  15 #include <linux/string.h>
  16 #include <linux/delay.h>
  17 #include <linux/init.h>
  18 #include <linux/fb.h>
  19 #include <linux/mm.h>
  20 #include <linux/of.h>
  21 #include <linux/platform_device.h>
  22
  23 #include <asm/io.h>
  24 #include <asm/fbio.h>
  25
  26 #include "sbuslib.h"
  27
  28 /*
  29  * Local functions.
  30  */
  31
  32 static int cg3_setcolreg(unsigned, unsigned, unsigned, unsigned,
  33                          unsigned, struct fb_info *);
  34 static int cg3_blank(int, struct fb_info *);
  35
  36 static int cg3_sbusfb_mmap(struct fb_info *info, struct vm_area_struct *vma);
  37 static int cg3_sbusfb_ioctl(struct fb_info *info, unsigned int cmd, unsigned long arg);
  38
  39 /*
  40  *  Frame buffer operations
  41  */
  42
  43 static const struct fb_ops cg3_ops = {
  44         .owner                  = THIS_MODULE,
  45         FB_DEFAULT_SBUS_OPS(cg3),
  46         .fb_setcolreg           = cg3_setcolreg,
  47         .fb_blank               = cg3_blank,
  48 };
  49
  50
  51 /* Control Register Constants */
  52 #define CG3_CR_ENABLE_INTS      0x80
  53 #define CG3_CR_ENABLE_VIDEO     0x40
  54 #define CG3_CR_ENABLE_TIMING    0x20
  55 #define CG3_CR_ENABLE_CURCMP    0x10
  56 #define CG3_CR_XTAL_MASK        0x0c
  57 #define CG3_CR_DIVISOR_MASK     0x03
  58
  59 /* Status Register Constants */
  60 #define CG3_SR_PENDING_INT      0x80
  61 #define CG3_SR_RES_MASK         0x70
  62 #define CG3_SR_1152_900_76_A    0x40
  63 #define CG3_SR_1152_900_76_B    0x60
  64 #define CG3_SR_ID_MASK          0x0f
  65 #define CG3_SR_ID_COLOR         0x01
  66 #define CG3_SR_ID_MONO          0x02
  67 #define CG3_SR_ID_MONO_ECL      0x03
  68
  69 enum cg3_type {
  70         CG3_AT_66HZ = 0,
  71         CG3_AT_76HZ,
  72         CG3_RDI
  73 };
  74
  75 struct bt_regs {
  76         u32 addr;
  77         u32 color_map;
  78         u32 control;
  79         u32 cursor;
  80 };
  81
  82 struct cg3_regs {
  83         struct bt_regs  cmap;
  84         u8      control;
  85         u8      status;
  86         u8      cursor_start;
  87         u8      cursor_end;
  88         u8      h_blank_start;
  89         u8      h_blank_end;
  90         u8      h_sync_start;
  91         u8      h_sync_end;
  92         u8      comp_sync_end;
  93         u8      v_blank_start_high;
  94         u8      v_blank_start_low;
  95         u8      v_blank_end;
  96         u8      v_sync_start;
  97         u8      v_sync_end;
  98         u8      xfer_holdoff_start;
  99         u8      xfer_holdoff_end;
 100 };
 101
 102 /* Offset of interesting structures in the OBIO space */
 103 #define CG3_REGS_OFFSET      0x400000UL
 104 #define CG3_RAM_OFFSET       0x800000UL
 105
 106 struct cg3_par {
 107         spinlock_t              lock;
 108         struct cg3_regs         __iomem *regs;
 109         u32                     sw_cmap[((256 * 3) + 3) / 4];
 110
 111         u32                     flags;
 112 #define CG3_FLAG_BLANKED        0x00000001
 113 #define CG3_FLAG_RDI            0x00000002
 114
 115         unsigned long           which_io;
 116 };
 117
 118 /**
 119  *      cg3_setcolreg - Optional function. Sets a color register.
 120  *      @regno: boolean, 0 copy local, 1 get_user() function
 121  *      @red: frame buffer colormap structure
 122  *      @green: The green value which can be up to 16 bits wide
 123  *      @blue:  The blue value which can be up to 16 bits wide.
 124  *      @transp: If supported the alpha value which can be up to 16 bits wide.
 125  *      @info: frame buffer info structure
 126  *
 127  * The cg3 palette is loaded with 4 color values at each time
 128  * so you end up with: (rgb)(r), (gb)(rg), (b)(rgb), and so on.
 129  * We keep a sw copy of the hw cmap to assist us in this esoteric
 130  * loading procedure.
 131  */
 132 static int cg3_setcolreg(unsigned regno,
 133                          unsigned red, unsigned green, unsigned blue,
 134                          unsigned transp, struct fb_info *info)
 135 {
 136         struct cg3_par *par = (struct cg3_par *) info->par;
 137         struct bt_regs __iomem *bt = &par->regs->cmap;
 138         unsigned long flags;
 139         u32 *p32;
 140         u8 *p8;
 141         int count;
 142
 143         if (regno >= 256)
 144                 return 1;
 145
 146         red >>= 8;
 147         green >>= 8;
 148         blue >>= 8;
 149
 150         spin_lock_irqsave(&par->lock, flags);
 151
 152         p8 = (u8 *)par->sw_cmap + (regno * 3);
 153         p8[0] = red;
 154         p8[1] = green;
 155         p8[2] = blue;
 156
 157 #define D4M3(x) ((((x)>>2)<<1) + ((x)>>2))      /* (x/4)*3 */
 158 #define D4M4(x) ((x)&~0x3)                      /* (x/4)*4 */
 159
 160         count = 3;
 161         p32 = &par->sw_cmap[D4M3(regno)];
 162         sbus_writel(D4M4(regno), &bt->addr);
 163         while (count--)
 164                 sbus_writel(*p32++, &bt->color_map);
 165
 166 #undef D4M3
 167 #undef D4M4
 168
 169         spin_unlock_irqrestore(&par->lock, flags);
 170
 171         return 0;
 172 }
 173
 174 /**
 175  *      cg3_blank - Optional function.  Blanks the display.
 176  *      @blank: the blank mode we want.
 177  *      @info: frame buffer structure that represents a single frame buffer
 178  */
 179 static int cg3_blank(int blank, struct fb_info *info)
 180 {
 181         struct cg3_par *par = (struct cg3_par *) info->par;
 182         struct cg3_regs __iomem *regs = par->regs;
 183         unsigned long flags;
 184         u8 val;
 185
 186         spin_lock_irqsave(&par->lock, flags);
 187
 188         switch (blank) {
 189         case FB_BLANK_UNBLANK: /* Unblanking */
 190                 val = sbus_readb(&regs->control);
 191                 val |= CG3_CR_ENABLE_VIDEO;
 192                 sbus_writeb(val, &regs->control);
 193                 par->flags &= ~CG3_FLAG_BLANKED;
 194                 break;
 195
 196         case FB_BLANK_NORMAL: /* Normal blanking */
 197         case FB_BLANK_VSYNC_SUSPEND: /* VESA blank (vsync off) */
 198         case FB_BLANK_HSYNC_SUSPEND: /* VESA blank (hsync off) */
 199         case FB_BLANK_POWERDOWN: /* Poweroff */
 200                 val = sbus_readb(&regs->control);
 201                 val &= ~CG3_CR_ENABLE_VIDEO;
 202                 sbus_writeb(val, &regs->control);
 203                 par->flags |= CG3_FLAG_BLANKED;
 204                 break;
 205         }
 206
 207         spin_unlock_irqrestore(&par->lock, flags);
 208
 209         return 0;
 210 }
 211
 212 static const struct sbus_mmap_map cg3_mmap_map[] = {
 213         {
 214                 .voff   = CG3_MMAP_OFFSET,
 215                 .poff   = CG3_RAM_OFFSET,
 216                 .size   = SBUS_MMAP_FBSIZE(1)
 217         },
 218         { .size = 0 }
 219 };
 220
 221 static int cg3_sbusfb_mmap(struct fb_info *info, struct vm_area_struct *vma)
 222 {
 223         struct cg3_par *par = (struct cg3_par *)info->par;
 224
 225         return sbusfb_mmap_helper(cg3_mmap_map,
 226                                   info->fix.smem_start, info->fix.smem_len,
 227                                   par->which_io,
 228                                   vma);
 229 }
 230
 231 static int cg3_sbusfb_ioctl(struct fb_info *info, unsigned int cmd, unsigned long arg)
 232 {
 233         return sbusfb_ioctl_helper(cmd, arg, info,
 234                                    FBTYPE_SUN3COLOR, 8, info->fix.smem_len);
 235 }
 236
 237 /*
 238  *  Initialisation
 239  */
 240
 241 static void cg3_init_fix(struct fb_info *info, int linebytes,
 242                          struct device_node *dp)
 243 {
 244         snprintf(info->fix.id, sizeof(info->fix.id), "%pOFn", dp);
 245
 246         info->fix.type = FB_TYPE_PACKED_PIXELS;
 247         info->fix.visual = FB_VISUAL_PSEUDOCOLOR;
 248
 249         info->fix.line_length = linebytes;
 250
 251         info->fix.accel = FB_ACCEL_SUN_CGTHREE;
 252 }
 253
 254 static void cg3_rdi_maybe_fixup_var(struct fb_var_screeninfo *var,
 255                                     struct device_node *dp)
 256 {
 257         const char *params;
 258         char *p;
 259         int ww, hh;
 260
 261         params = of_get_property(dp, "params", NULL);
 262         if (params) {
 263                 ww = simple_strtoul(params, &p, 10);
 264                 if (ww && *p == 'x') {
 265                         hh = simple_strtoul(p + 1, &p, 10);
 266                         if (hh && *p == '-') {
 267                                 if (var->xres != ww ||
 268                                     var->yres != hh) {
 269                                         var->xres = var->xres_virtual = ww;
 270                                         var->yres = var->yres_virtual = hh;
 271                                 }
 272                         }
 273                 }
 274         }
 275 }
 276
 277 static u8 cg3regvals_66hz[] = { /* 1152 x 900, 66 Hz */
 278         0x14, 0xbb,     0x15, 0x2b,     0x16, 0x04,     0x17, 0x14,
 279         0x18, 0xae,     0x19, 0x03,     0x1a, 0xa8,     0x1b, 0x24,
 280         0x1c, 0x01,     0x1d, 0x05,     0x1e, 0xff,     0x1f, 0x01,
 281         0x10, 0x20,     0
 282 };
 283
 284 static u8 cg3regvals_76hz[] = { /* 1152 x 900, 76 Hz */
 285         0x14, 0xb7,     0x15, 0x27,     0x16, 0x03,     0x17, 0x0f,
 286         0x18, 0xae,     0x19, 0x03,     0x1a, 0xae,     0x1b, 0x2a,
 287         0x1c, 0x01,     0x1d, 0x09,     0x1e, 0xff,     0x1f, 0x01,
 288         0x10, 0x24,     0
 289 };
 290
 291 static u8 cg3regvals_rdi[] = {  /* 640 x 480, cgRDI */
 292         0x14, 0x70,     0x15, 0x20,     0x16, 0x08,     0x17, 0x10,
 293         0x18, 0x06,     0x19, 0x02,     0x1a, 0x31,     0x1b, 0x51,
 294         0x1c, 0x06,     0x1d, 0x0c,     0x1e, 0xff,     0x1f, 0x01,
 295         0x10, 0x22,     0
 296 };
 297
 298 static u8 *cg3_regvals[] = {
 299         cg3regvals_66hz, cg3regvals_76hz, cg3regvals_rdi
 300 };
 301
 302 static u_char cg3_dacvals[] = {
 303         4, 0xff,        5, 0x00,        6, 0x70,        7, 0x00,        0
 304 };
 305
 306 static int cg3_do_default_mode(struct cg3_par *par)
 307 {
 308         enum cg3_type type;
 309         u8 *p;
 310
 311         if (par->flags & CG3_FLAG_RDI)
 312                 type = CG3_RDI;
 313         else {
 314                 u8 status = sbus_readb(&par->regs->status), mon;
 315                 if ((status & CG3_SR_ID_MASK) == CG3_SR_ID_COLOR) {
 316                         mon = status & CG3_SR_RES_MASK;
 317                         if (mon == CG3_SR_1152_900_76_A ||
 318                             mon == CG3_SR_1152_900_76_B)
 319                                 type = CG3_AT_76HZ;
 320                         else
 321                                 type = CG3_AT_66HZ;
 322                 } else {
 323                         printk(KERN_ERR "cgthree: can't handle SR %02x\n",
 324                                status);
 325                         return -EINVAL;
 326                 }
 327         }
 328
 329         for (p = cg3_regvals[type]; *p; p += 2) {
 330                 u8 __iomem *regp = &((u8 __iomem *)par->regs)[p[0]];
 331                 sbus_writeb(p[1], regp);
 332         }
 333         for (p = cg3_dacvals; *p; p += 2) {
 334                 u8 __iomem *regp;
 335
 336                 regp = (u8 __iomem *)&par->regs->cmap.addr;
 337                 sbus_writeb(p[0], regp);
 338                 regp = (u8 __iomem *)&par->regs->cmap.control;
 339                 sbus_writeb(p[1], regp);
 340         }
 341         return 0;
 342 }
 343
 344 static int cg3_probe(struct platform_device *op)
 345 {
 346         struct device_node *dp = op->dev.of_node;
 347         struct fb_info *info;
 348         struct cg3_par *par;
 349         int linebytes, err;
 350
 351         info = framebuffer_alloc(sizeof(struct cg3_par), &op->dev);
 352
 353         err = -ENOMEM;
 354         if (!info)
 355                 goto out_err;
 356         par = info->par;
 357
 358         spin_lock_init(&par->lock);
 359
 360         info->fix.smem_start = op->resource[0].start;
 361         par->which_io = op->resource[0].flags & IORESOURCE_BITS;
 362
 363         sbusfb_fill_var(&info->var, dp, 8);
 364         info->var.red.length = 8;
 365         info->var.green.length = 8;
 366         info->var.blue.length = 8;
 367         if (of_node_name_eq(dp, "cgRDI"))
 368                 par->flags |= CG3_FLAG_RDI;
 369         if (par->flags & CG3_FLAG_RDI)
 370                 cg3_rdi_maybe_fixup_var(&info->var, dp);
 371
 372         linebytes = of_getintprop_default(dp, "linebytes",
 373                                           info->var.xres);
 374         info->fix.smem_len = PAGE_ALIGN(linebytes * info->var.yres);
 375
 376         par->regs = of_ioremap(&op->resource[0], CG3_REGS_OFFSET,
 377                                sizeof(struct cg3_regs), "cg3 regs");
 378         if (!par->regs)
 379                 goto out_release_fb;
 380
 381         info->fbops = &cg3_ops;
 382         info->screen_base = of_ioremap(&op->resource[0], CG3_RAM_OFFSET,
 383                                        info->fix.smem_len, "cg3 ram");
 384         if (!info->screen_base)
 385                 goto out_unmap_regs;
 386
 387         cg3_blank(FB_BLANK_UNBLANK, info);
 388
 389         if (!of_property_present(dp, "width")) {
 390                 err = cg3_do_default_mode(par);
 391                 if (err)
 392                         goto out_unmap_screen;
 393         }
 394
 395         err = fb_alloc_cmap(&info->cmap, 256, 0);
 396         if (err)
 397                 goto out_unmap_screen;
 398
 399         fb_set_cmap(&info->cmap, info);
 400
 401         cg3_init_fix(info, linebytes, dp);
 402
 403         err = register_framebuffer(info);
 404         if (err < 0)
 405                 goto out_dealloc_cmap;
 406
 407         dev_set_drvdata(&op->dev, info);
 408
 409         printk(KERN_INFO "%pOF: cg3 at %lx:%lx\n",
 410                dp, par->which_io, info->fix.smem_start);
 411
 412         return 0;
 413
 414 out_dealloc_cmap:
 415         fb_dealloc_cmap(&info->cmap);
 416
 417 out_unmap_screen:
 418         of_iounmap(&op->resource[0], info->screen_base, info->fix.smem_len);
 419
 420 out_unmap_regs:
 421         of_iounmap(&op->resource[0], par->regs, sizeof(struct cg3_regs));
 422
 423 out_release_fb:
 424         framebuffer_release(info);
 425
 426 out_err:
 427         return err;
 428 }
 429
 430 static void cg3_remove(struct platform_device *op)
 431 {
 432         struct fb_info *info = dev_get_drvdata(&op->dev);
 433         struct cg3_par *par = info->par;
 434
 435         unregister_framebuffer(info);
 436         fb_dealloc_cmap(&info->cmap);
 437
 438         of_iounmap(&op->resource[0], par->regs, sizeof(struct cg3_regs));
 439         of_iounmap(&op->resource[0], info->screen_base, info->fix.smem_len);
 440
 441         framebuffer_release(info);
 442 }
 443
 444 static const struct of_device_id cg3_match[] = {
 445         {
 446                 .name = "cgthree",
 447         },
 448         {
 449                 .name = "cgRDI",
 450         },
 451         {},
 452 };
 453 MODULE_DEVICE_TABLE(of, cg3_match);
 454
 455 static struct platform_driver cg3_driver = {
 456         .driver = {
 457                 .name = "cg3",
 458                 .of_match_table = cg3_match,
 459         },
 460         .probe          = cg3_probe,
 461         .remove         = cg3_remove,
 462 };
 463
 464 static int __init cg3_init(void)
 465 {
 466         if (fb_get_options("cg3fb", NULL))
 467                 return -ENODEV;
 468
 469         return platform_driver_register(&cg3_driver);
 470 }
 471
 472 static void __exit cg3_exit(void)
 473 {
 474         platform_driver_unregister(&cg3_driver);
 475 }
 476
 477 module_init(cg3_init);
 478 module_exit(cg3_exit);
 479
 480 MODULE_DESCRIPTION("framebuffer driver for CGthree chipsets");
 481 MODULE_AUTHOR("David S. Miller <davem@davemloft.net>");
 482 MODULE_VERSION("2.0");
 483 MODULE_LICENSE("GPL");